I looked in the current Brownells catalog and they have Krag/Springfield screws in stock.
Also found some more photos on my computer, these were from making the extractor cut in the barrel. The cutter was made from a beat up woodruff key tool. Two edges were ground to roughly the same profile as the original and the other edges were ground off for simplicity.
Some info from earlier posts if someone is also doing this:
"The slot itself is not centered and the radius on the bottom is not centered. I measured the radius on the extractor and it is 13/64 and matches the radius in the bottom of the slot.
The cut is at a 34 degree angle, so I have that down. "
After I posted this I gave the extractor a hard look put it back on the bolt. It was a piece of cake getting the offset measurements off the extractor.
  " For anyone else rebarreling a Krag, the offset of extractor cut is .029 to .030" or .75mm. The radius on the extractor is in the middle of the case when everything is assembled so the offset of the radius is the same. A person could put a flat bottomed cut in the barrel but it would have to be a little deeper. This would probably be safe as the case is very thick in that are and unlikely to blow out."

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